In the dental art, the use of a dental coating composition is generally desirable for a wide variety of applications, such as etching or bleaching. To attain proper application at the desired location, it is desirable that the composition be controllable and slow to flow away from the target site. Thus a high viscosity dental composition in the oral environment would be quite useful.
Currently available dental compositions are provided in seemingly extreme viscosity states. That is, there exist compositions that have very low viscosities as well as compositions that are highly thickened and therefore possess high viscosity. Those with low viscosities are difficult to control and have tendencies to flow away from the target site once they are applied. Compositions with high viscosities are difficult to extrude through a small orifice.
Certain dental compositions may use thickeners such as fumed silica and polyvinyl alcohols. Problems encountered in using these thickeners include aging, which results in non-homogenous gels which make handling difficult, and shear thinning, which reduces the viscosity of a gel when extruded through an orifice and thinning at elevated temperatures. Thinning can result in a material that drips from the orifice and that may fail to remain localized at the desired point of application.